1. Field of the Invention
The present invention relates to an amine composition for emulsifier for bitumen which can easily be handled and which is liquid at ordinary temperature. More specifically, the present invention relates to a liquid amine composition which is a precursor of an emulsifier for emulsifying a bituminous materials such as asphalt and which is excellent in handling properties and which can impart, to a finally emulsified bituminous materials, more excellent emulsifying stability and adhesive properties to aggregates than conventional products.
2. Prior Art
Amine compounds each having a hydrocarbon group of at least 8 carbon atoms have been widely used in various industrial applications, because cationic surface active agents derived from the amine compounds can exert excellent properties. For example, these amine compounds are useful as aqueous emulsifying agents for bituminous materials, i.e., viscous solid like oils called petroleum asphalts, bitumens and the like in applications of a road pavement material, a waterproof material for a shore bank, and a roofing material. Furthermore, it is also known that these amine compounds are useful as a floating separation agent for minerals, an antistatic agent for polymers, fibers and the like, a corrosion inhibitor for metals, and an anticoagulant for fertilizers.
In order to exert the excellent properties of the amine compounds in these applications, high adsorbing properties to an object are required, and thus, the amine compounds each having a long chain hydrocarbyl group have been preferably used. However, most of such amine compounds are solid at room temperature, and so, it is inconvenient to handle them. Therefore, for the liquefaction of these amine compounds, various investigations have been heretofore conducted. Such a handling problem is particularly noticeable in winter and in cold districts.
For example, in U.S. Pat. Nos. 4,496,474 and 5,098,604, for the purpose of lowering a melting point, it has been disclosed to use alkyl ether amine, branched alkyl amine, or an oxyalkylated amine which have a poor crystalization property. In such a case, however, there is a disadvantage that the cationic surface activity deteriorates, and even if the amount of the amine is increased, the excellent characteristics which the solid amine has cannot be exerted on occasion.
Furthermore, in JP-A 59-123523, a liquid amine composition containing an aliphatic amine and a specific carboxylic acid has been disclosed. This liquid amine composition is liquid even at a low temperature, and in the case that the liquid amine composition is used as a cationic surface active agent, an amine hydrochloride is formed by adding a strong acid such as hydrochloric acid, so that it is possible to obtain almost the same performance as the original solid amine.
It is not known in the state of arts what relation should take place between an amine composition, emulsion stability of bituminous materials and adhesion performance of bituminous materials. With the aggrandizement of weight of cars and the speed up of cars in recent years, higher adhesive properties to aggregates have been strongly required. This is the reason why harder asphalts having a small penetration have been widely used. However, such conventional products do not always satisfy the required performance.